el-Sonbaty S S, Watanabe M, Hochito K, Yamaguchi K, Matsuda I, Tsuchiya H
Department of Pediatrics, Kumamoto University School of Medicine, Japan.
Int J Hematol. 1995 Feb;61(2):61-8. doi: 10.1016/0925-5710(95)00352-s.
Human granulocyte colony-stimulating factor (G-CSF) receptor cDNA was introduced into the erythroleukemic cell line K562, which normally does not express the receptor, using lipofection transfection of a G-CSF receptor expression plasmid vector. Transfected cells expressed the receptor with a dissociation constant of 130 pmol/L, and a maximum of 11,800 binding sites per cell. Culture of G-CSF receptor-expressing cells (GR-K562) in the presence of G-CSF enhanced DNA synthesis and a stimulation index of 4.61 was obtained in a 3H-thymidine uptake assay. Furthermore, flow cytometric studies revealed induced expression of CD11b (29% from 7%), and enhanced expression of CD13 (57% from 27%) on GR-K562 cultured in the presence of G-CSF. Our findings indicate that the exogenously expressed G-CSF receptor can deliver signals and function efficiently on these immature cells on which the receptor is not normally expressed, which suggests the presence of intact intracellular signal transduction pathways that can be used by the ectopically expressed receptor.
利用脂质体转染 G-CSF 受体表达质粒载体，将人粒细胞集落刺激因子（G-CSF）受体 cDNA 导入通常不表达该受体的红白血病细胞系 K562 中。转染后的细胞表达该受体，解离常数为 130 pmol/L，每个细胞最多有 11,800 个结合位点。在 G-CSF 存在的情况下培养表达 G-CSF 受体的细胞（GR-K562），可增强 DNA 合成，在 3H-胸苷摄取试验中获得的刺激指数为 4.61。此外，流式细胞术研究显示，在 G-CSF 存在下培养的 GR-K562 上，CD11b 的表达诱导增加（从 7%增至 29%），CD13 的表达增强（从 27%增至 57%）。我们的研究结果表明，外源性表达的 G-CSF 受体能够在这些正常情况下不表达该受体的未成熟细胞上有效地传递信号并发挥功能，这表明存在完整的细胞内信号转导途径，可被异位表达的受体利用。
